A three-dimensional (3D) model scanning technique is mainly used to obtain 3D information of an object, and reconstruct a 3D model on an electronic device capable of performing computations such as a computer or a handheld device, etc. Compared to a model produced by an art staff by using model edit software (for example, Maya or 3DMax), not only an appearance of the 3D model has a higher fidelity, but also it has less fabrication time and low manpower demand.
The existing 3D model scanning technique mainly includes two core steps of “shooting” and “merging” images of an object. For example, in the “shooting” step, a shooting angle of the object has to cover all possible angles as far as possible in order to guarantee integrity of a final result. After the “shooting” step is completed, the “merging” step is executed to merge images captured in different angles into a 3D model. In the two core steps, the “merging” step is generally the most difficult step, and the largest difference in the existing techniques also lies in such step.
For example, one of the existing techniques is to use a single camera to obtain shooting results of different time points, and calculate correlation of the shooting results according to a feature corresponding relationship of overlapped parts of the shooting results, so as to merge the shooting results to build a 3D model of the object. Alternatively, another existing technique is to use a single camera and a turntable to record a rotating angle of a turntable corresponding to a shooting moment, and merge the shooting results of each angle obtained by the turntable, so to build the 3D model of the object. Moreover, another existing technique is to erect a plurality of cameras to cover all of the shooting angles, and simultaneously obtain shooting results of the object. Since positions of the cameras are all fixed, as long as a position and a shooting direction of each camera are obtained, shooting data of the cameras can be merged to build the 3D model of the object.
However, in the above existing techniques, since the single camera shoots the object at different time points, if an appearance of the object changes during the shooting period, the reconstructed model of the object is incomplete (for example, structure misalignment caused by change of the structure). Moreover, if a plurality of cameras are used to simultaneously shoot the object, the required cost is higher than the cost of using the single camera, which is difficult to be accepted by ordinary users.
Therefore, it is an important problem to be resolved by manufactures to accurately reconstruct a 3D model of a deformable object.